Tweezers



A. L. BETTON July 5, 1960 TWEEZERS Filed Feb. 28, 1957 Aim/04o L-flErra/v,

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TWEEZERS Arnold L. Betton, 2851 Cochran St., Los Angeles 16, Calif.

Filed Feb. 28, 1957, Ser. No. 649,274

3 Claims. or. 81-43) This invention relates to tweezers and moreparticularly to a tool of this type which has a reverse action.

Tweezers having a reverse action are typically complicated mechanisms,expensive of manufacture and unsuited for the handling of small articlessuch as tiny jewels and crystals, this in part because a continualgripping force must be expended by the operator. Another shortcomingtypical of prior art tweezers, either conventional action or reverseaction, is their tendency to eX-.

These tweezers, typically because of their inherent design, cannot beused for fine watchmaking. They further are not suitable for use in theelectronics industry such as the semiconductor field. In the latterindustry it is often necessary to lift and transport very finecomponents such as fine wires and crystals of germanium or silicon,whose greatest dimension does not exceed .030 inch. No more than theslightest amount of play in the tips of the ends of the tweezers, i.e.,of the very gripping surfaces can be tolerated, else the objects beinghandled may very well be damaged or even be inadvertently released fromthe jaws of the tweezers.

Another diificulty attendant with prior art tweezers is the lack of anadjustment mechanism. This is necessary due to the fact that, aftercontinued use, play may develop between the jaws of the tweezers.

The present invention overcomes the above disadvantages and otherdifficulties encountered in prior art reverse action tweezers.

tion there is provided a tweezer of standard design whose between theends of the arms.

. States M61111 vided an accordionlike fiat spring joined to the inner 1surfaces of each arm at a point near the open gripping jaws of thetweezers.

In another embodiment of the present invention, a set screw is providednear the closed end of the tweezers whichscrew fits into a threaded holewithin one arm of the tweezers to permit the set screw to controllablyforce apart the two arms.

It is therefore an object of the present invention to pro- 7 PatentedJuly 5, 1960 vide a tweezer having an improved reverse actionmecharendering it relatively uncostly of manufacture. 7

Still another object of the present invention is to provide an improvedtype of reverse action tweezers which may be adopted from a conventionaltweezer.

Yet another object of the present invention is to provide a reverseaction tweezer with a controlled gripping force adjustment.

The novel features which are believed to be characteristic of thepresent invention both as to its organization and method of operation,together with further objects and advantages thereof, will be betterunderstood from the following description considered in connection withthe accompanying drawing .in which two embodiments of the presentinvention are illustrated by way of example only, and are not intendedas a definition of the limits of the invention.

In the drawing:

Figure 1 is a perspective view of the presently preferred embodiment ofthe tweezers of this invention;

Figure 2 is a top plan view of the tweezers of Figure 1;

Figure 3 is an exploded sectional view taken along line 3-3 of Figure 2;

Figure 4 is a view in perspective of an alternate embodiment of thetweezers of the present invention; and

Figure 5 is a view in perspective showing how the set screw of thetweezers in Figures 1 and 2 may be employed in conventional tweezers.

Referring now to the drawing there is shown in Figure 1 the presentlypreferred embodiment of the reverse action tweezers of the presentinvention as it might be gripped by the hand of an operator during use.The tweezer consists of two resilient arms, 11 and 12 which areconnected at the rear as at 15. As in the case of ordinary tweezers thearms 11 and 12 diverge from the closed end 15 when it is in the unloadedposition. However, herein, in order to impart the reverse action, i.e.,have tweezer jaws 18 and 19 closed when no pressure is applied to thearms, an accordionlike spring 14 is aflixed between the inner faces ofthe arms 11 and 12. Further, at regions 22 and 23 as shown in Figure 2,the arms 11 and 12 are of decreased thickness in order to increase theresiliency thereof. Regions 22 and 23 preferably, but not necessarily,commence at a point substanby the inventor although this is notanecessary, design limitation. 1 v

Thus, it will readily appear that with a relatively small gripping forcebeing applied to. regions 22 and 23.

of arms 11 and 12, that the jaws 18 and 19 will be forced open with thespring 14 acting as a fulcrum. ,In Figure 2 there is shown in phantomlines, the action of the tweezers upon being squeezed at 22 and 23 toopen jaws 18 and 19 to permit gripping of component Making regionsAccordionlike spring 14'should preferably be made 1 of cold rolled steelin order to render it impervious to acids and the like, but any otherresilient metal will sufiice. Further, spring 14 may be attached to arms11 and 12 by welding, soldering or the like. The number of folds, thethickness of the sheet, its positioning relative to jaws 18 and 19 andthe particular material of spring 14 will of course depend upon the usecontemplated for the tweezers. Generally speaking, the closer thatspring 14'is placed to jaws 18 and 19 the looser will be the grip of thejaws and the greater will be their opening when portions 22 and 23 aresqueezed. And of course the closer that spring 14 is located towards end15 the wider will jaws 18 and 19 be opened. Further, rigid alignment ofjaws 18. and 19 is assured by spring 14 as the jaws cannot then move in.a planeparallel with the fiat part of the tweezer arms. These parameterswill easily be resolved by one skilled in the art.

It should further be noted that the exact position, the length and thethickness of portions 22 and 23 will also have an appreciable effectupon the magnitude of the gripping force exerted upon the jaws 18 and19. With thinner portions 22 and 23 there will be less tension upon jaws18 and 19, and the closer portions 22 and 23 are toward the rear 15 ofthe tweezers, the less tension will be exterted upon jaws 18 and 19.Again these parameters, depending upon the size of the tweezers and thematerials used, can easily be determined by one skilled in the art.

Finally set screw 16 is provided at the rear of the tweezers to permitof controllable adjustment in the force exerted at the gripping jaws 18and 19. It has been found that screw 16 should be placed from to /8"from the opening of end 15, the point of opening being designated as 30.As screw 16 is tightened there is a tendency for the jaws 18 and 19 tobe drawn more closely together while a loosening of the screw will havean opposite effect. This adjustment feature is particularly advantageouswhen components of varying sizes are to be handled. It is also ofadvantage to take up any play between the jaws which will typicallyresult after prolonged use of the tweezers. Set screw 16 is merelyscrewed into a threaded hole in one arm, herein 11, which hole islocated near the closed end 15 so that it willbear on the opposite arm,herein 12.

From the drawing of the tweezers as presented in Figures 1 and 2 it isapparent that a conventional tweezers can be easily be adapted to thedesign of that of this invention. That is thinned portions 22 and 23 maybe produced by grinding away of the metal or the like to produce thethinning required. Accordionlike spring 14 can easily be insertedbetween the inside surfaces of arms 11 and 12. Finally, adjustment setscrew 16 can then be provided for by drilling and tapping a hole in arm11.

In Figure 4 there is shown an embodiment of the present inventionwithout the set screw improvement of the Figure l and Figure 2 device.Herein the arms are also designated 22 and 23.

Finally, in Figure 5 there is shown an illustration of how the set screw16 may be used in a conventional type tweezer to permit of greater rangeof grip. opening and to compensate for play in much the same manner asdiscussed hereinabove with respect to the reverse action tweezer ofFigures 1 and 2. Unlike the Figure 4 embodiment, there are nothinnedportions in arms herein designated 25a and 26a.

There has thus been described a new and improved reverse action tweezerwhich incorporates simplicity of design and which. inherently has littleor no play between its gripping jaws.

What is claimed as new is:

1. A reverse action tweezer comprising: a pair of resilient'armsconnected 'at one end and terminating in gripping jaws at the other end,each" of said arms having a first predetermined thickness from saidconnected end to a first pointapproximately midway between saidconnected end and said other end, each of said arms having a second andlesser thickness commencing from said first point and terminating at asecond point, said second point being located intermediate said firstpoint and said gripping jaws, and an accordionlike spring connectedbetween the inner surfaces of said arms in the vicinity of said secondpoint.

2. A reverse action tweezer comprising: a pair of substantially parallelresilient arms connected at one end and terminating in gripping jaws atthe other end, said N arms being of a predetermined thickness; a regionof reduced thickness in said arms, said region extending from a firstpoint on said arms and terminating at a second point proximate the rearof said jaws, said two points being separated by a distanceapproximately one-third the length of said arms; and a spring securedbetween the inner surfaces of said arms in the vicinity of said secondpoint.

3. A reverse action tweezer comprising: a pair of resilient armsconnected at one end and terminating in gripping jaws at thev other end,each of said arms having a first predetermined thickness from saidconnected end to, a first point approximately midway between saidconnected end and said other end, each of said arms having a second andlesser thickness commencing from said first point and terminating at asecond point, said second point being located intermediate said firstpoint and said gripping jaws; a spring connected between the innersurfaces of said arms in the vicinity of said second point; andadjustment means located between said first point and said connected endto control the gripping force between said gripping jaws.

4. A reverse action tweezer comprising: a pair of resilient armsconnected at one end and terminating in gripping jaws at the other end,each of said arms having a first predetermined thickness from saidconnected end to a first point, each of said arms having a second andlesser thickness commencing from said first point and terminating at asecond point, said second point being located intermediate said firstpoint and said gripping jaws; and a spring connected between the innersurfaces of said arms in the vicinity of said second point.

5. A reverse action tweezer comprising: a pair of resilient armsconnected at one end and terminating in gripping jaws at the other end,each of said arms having a first predetermined thickness from saidconnected end to a first point approximately midway between saidconnected end and said other end, each of said arms having a second andlesser thickness commencing from said first point and terminating at asecond point, said second point being located intermediate said firstpoint and gripping jaws; an accordionlike spring connected between theinner surfaces of said arms in the vicinity of said second point; andadjustment means located between said first point and said connectedends to control the gripping force between said gripping jaws.

6. A reverse action tweezer comprising: a pair of substantially parallelresilient arms connected at one end and terminating in gripping jaws atthe other end, said arms being of a predetermined thickness; a region ofreduced thickness in said arms, said, region extending from a firstpoint on said arms and terminating at a second point proximate the rearof said jaws; and a spring secured between the inner surfaces of saidarms in the vicinity of said second point.

7. A reverse action tweezer comprising: a pair of resilient arm members,each having a jaw at one end shaped to facilitate gripping relativelysmall articles, said arms being permanently connected at the other end;each of said arms having a relatively thin portion intermediate the endsthereof; and a spring fastened to said thin port-ions and between saidarms at a point proximate the jaw end-of said thin portion.

bers to control the gripping force between said gripping jaws.

References Cited in the file of this patent UNITED STATES PATENTS WillsAug. 15, 1882 Parker June 2, 1896 Clarkson May 4, 1897 Carlsen May 10,1904 Siptrott Oct. 26, 1948

